In recent years, the upswing in drilling activity and the higher price of natural gas has caused the industry to focus more on non-conventional gas reservoirs. Heading up this list are gas shales. This peaked interest was brought on not only by an increase in natural gas prices, but also the apparent abundance of potential gas shales present in the continental United States and the well publicized success of the Barnett Shale of North Texas. In order to obtain commercial production from these low permeability shale reservoirs, fracture stimulation is required. Numerous technical papers have been published on the merits and success of stimulation in this well documented reservoir. While slickwater treatments have become the stimulation method of choice, it is important to note that several other stimulation and completion techniques have been employed that have resulted in economic and commercially viable Barnett Shale producers over the last 20 years. Although there has been tremendous success with slickwater fracture treatments, many believe this technology can be universally applied to all gas shale reservoirs. While this may be the case in the Barnett Shale it is not necessarily true for other prospective shale basins being explored.

This paper will include a brief history of Barnett Shale stimulation practices and go on to address shale reservoirs and characteristics that make each one unique from a stimulation perspective. It is not the attempt of the authors to provide a stimulation checklist, but to identify a number of shale reservoir characteristics and their effect on the process of stimulation optimization. Case histories in the Ft. Worth Barnett and Permian Basin Barnett and Woodford Shales will be used to infer key differences in reservoir attributes and how these differences influence stimulation decisions.

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